Twelve different video games showing substance use were observed and the duration times of game play ( in seconds) are listed below. The design of the study justifies the assumption that the sample can be treated as a simple random sample. use the data to construct a 95% confidence interval estimate of mean duration of game play.

Question

Twelve different video games showing substance use were observed and the duration times of game play ( in seconds) are listed below. The design of the study justifies the assumption that the sample can be treated as a simple random sample. use the data to construct a 95% confidence interval estimate of mean duration of game play. 
4061,3886,3865,4023,4309,4821,4645,4021,5024,4812,4331,4325

PsyDAG · Answer

Find the mean first = sum of scores/number of scores

Subtract each of the scores from the mean and square each difference. Find the sum of these squares. Divide that by the number of scores to get variance.

Standard deviation = square root of variance

95% = mean ± 1.96 SEm

SEm = SD/√n

I'll let you do the calculations.